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INTRODUCTION
============
mp3encode is a package for encoding MPEG layer I, II and III audio
files. This is the reference implementation so don't expect
spectacular performance.
Driving encode is pretty simple although it may take some practice to
work out an optimal compression rate. AIFF files are the only type of
files that seem to work with this version so you may need to install a
port like "sox" to convert your file types. I use the "nas" port to
record and edit all of my audio files but so long as you have a valid
AIFF file it shouldn't matter what you use.
Although the source code includes a decoder I have decided not to port
it because we already have a couple of top class mpeg decoders in the
ports collection.
HINTS & TIPS
============
Physcoacoustic model 2 is the only supported model in layer III
encoding. A bit-rate of 128Kbps is adequate for most forms of music but
you may need to turn down the compression to 160Kbps if the music is
particularly atmospheric.
Vocal spoken recordings are best encoded using a 32Kbps bit-rate with
layer II (layer III makes you sound like a Dalek under digital water)
with a 32kHz sample rate in mono. Using this method I have managed to
get about 5 minutes of AM Radio quality audio into around 1 MB.
MISC
====
If anyone finds any bugs in this software please let me know and
include patches to fix them.
Share and enjoy,
Joel...
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